Abstract: A key-operated electrical switch assembly is provided and is designed primarily to be used in conjunction with the electrical system of an automobile or truck as a means to provide a source of electric power. This assembly was devised primarily for use with alternator powered electrical systems, as are now utilized in most automotive vehicles. Furthermore, it is designed and constructed in such a manner that the assembly could not be left in an "on" position if one desired to retain the security of the key.